/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.classfile.editor;

import a.annotation.proguard.classfile.attribute.annotation.*;
import proguard.classfile.*;
import proguard.classfile.attribute.annotation.visitor.AnnotationVisitor;
import proguard.classfile.util.SimplifiedVisitor;

/**
 * This AnnotationVisitor adds all annotations that it visits to the given target annotation element value, target
 * annotation attribute, or target parameter annotation attribute.
 *
 * @author Eric Lafortune
 */
public class AnnotationAdder extends SimplifiedVisitor implements AnnotationVisitor {
    private static final ElementValue[] EMPTY_ELEMENT_VALUES = new ElementValue[0];

    private final ProgramClass targetClass;
    private final AnnotationElementValue targetAnnotationElementValue;
    private final AnnotationsAttributeEditor annotationsAttributeEditor;
    private final ParameterAnnotationsAttributeEditor parameterAnnotationsAttributeEditor;

    private final ConstantAdder constantAdder;

    /**
     * Creates a new AnnotationAdder that will copy annotations into the given target annotation element value.
     */
    public AnnotationAdder(ProgramClass targetClass, AnnotationElementValue targetAnnotationElementValue) {
        this.targetClass = targetClass;
        this.targetAnnotationElementValue = targetAnnotationElementValue;
        this.annotationsAttributeEditor = null;
        this.parameterAnnotationsAttributeEditor = null;

        constantAdder = new ConstantAdder(targetClass);
    }

    /**
     * Creates a new AnnotationAdder that will copy annotations into the given target annotations attribute.
     */
    public AnnotationAdder(ProgramClass targetClass, AnnotationsAttribute targetAnnotationsAttribute) {
        this.targetClass = targetClass;
        this.targetAnnotationElementValue = null;
        this.annotationsAttributeEditor = new AnnotationsAttributeEditor(targetAnnotationsAttribute);
        this.parameterAnnotationsAttributeEditor = null;

        constantAdder = new ConstantAdder(targetClass);
    }

    /**
     * Creates a new AnnotationAdder that will copy annotations into the given target parameter annotations attribute.
     */
    public AnnotationAdder(ProgramClass targetClass,
        ParameterAnnotationsAttribute targetParameterAnnotationsAttribute) {
        this.targetClass = targetClass;
        this.targetAnnotationElementValue = null;
        this.annotationsAttributeEditor = null;
        this.parameterAnnotationsAttributeEditor =
            new ParameterAnnotationsAttributeEditor(targetParameterAnnotationsAttribute);

        constantAdder = new ConstantAdder(targetClass);
    }

    // Implementations for AnnotationVisitor.

    public void visitAnnotation(Clazz clazz, Annotation annotation) {
        Annotation newAnnotation = new Annotation(constantAdder.addConstant(clazz, annotation.u2typeIndex), 0,
            annotation.u2elementValuesCount > 0 ? new ElementValue[annotation.u2elementValuesCount]
                : EMPTY_ELEMENT_VALUES);

        // TODO: Clone array.
        newAnnotation.referencedClasses = annotation.referencedClasses;

        // Add the element values.
        annotation.elementValuesAccept(clazz, new ElementValueAdder(targetClass, newAnnotation, false));

        // What's the target?
        if (targetAnnotationElementValue != null) {
            // Simply set the completed annotation.
            targetAnnotationElementValue.annotationValue = newAnnotation;
        } else {
            // Add the completed annotation.
            annotationsAttributeEditor.addAnnotation(newAnnotation);
        }
    }

    public void visitAnnotation(Clazz clazz, Method method, int parameterIndex, Annotation annotation) {
        Annotation newAnnotation = new Annotation(constantAdder.addConstant(clazz, annotation.u2typeIndex), 0,
            annotation.u2elementValuesCount > 0 ? new ElementValue[annotation.u2elementValuesCount]
                : EMPTY_ELEMENT_VALUES);

        // TODO: Clone array.
        newAnnotation.referencedClasses = annotation.referencedClasses;

        // Add the element values.
        annotation.elementValuesAccept(clazz, new ElementValueAdder(targetClass, newAnnotation, false));

        // Add the completed annotation.
        parameterAnnotationsAttributeEditor.addAnnotation(parameterIndex, newAnnotation);
    }
}